A connector or coupler is used for electrically connecting two devices so as to pass a signal. A connector may include a female metal contact on one side, which engages with a male metal contact on the other side. However, such connectors may suffer from the following problems:
1. The connection performance may degrade due to oxidation and wear after time.
2. When the data rate is ultra high (>10 Gb/s) the area of each contact becomes very small.
3. The small mechanical parts are very easily damaged.
4. The fabrication is expensive.
An alternative to metal connectors 1s a wireless signal connection. However, a wireless connection is less ideal due to electromagnetic interference (EMI) and limited frequency resource. A further promising alternative is a dielectric connector, for example U.S. Pat. No. 7,481,672. However, such prior art dielectric connectors are mainly useful for DC isolation and still suffer from EMI problems, especially in the unconnected state. EMI problems can relate to the device being overly susceptible to interference from other devices, and/or that the device causes excessive interference in other devices.